The long-term goal of this project is to develop a minimally invasive treatment for cancers in the upper abdomen, including primary and metastatic tumors in the liver, and renal cell carcinoma. High intensity focused ultrasound (HIFU) is a promising technique for the next generation of non-invasive cancer therapy systems. With this technology, ultrasound energy is focused at a point deep within the body to thermally ablate targeted tissue. This can be done with minimal heat deposition at the skin surface and without skin puncture or incision. Magnetic resonance imaging (MRI) can provide tissue temperature, and, therefore, the means to precisely target thermal energy to target tissues. The significance of this project is that it would provide a non-invasive treatment option for cancers of the upper abdomen. Colorectal cancer is the third leading cause of cancer related deaths in men and women. Many of these deaths are associated with colorectal metastases to the liver. Similarly, renal cell carcinoma and heptatocellular carcinoma are often fatal malignancies which are increasing in incidence in the US. Minimally invasive thermal therapies are showing promising results in the treatment of these conditions, but many technical challenges remain. The work proposed here addresses many of these challenges and if successful, will represent a major advance in the non-invasive treatment of cancer.